Self-contained type hydraulic valve lifter



\U\ r Feb. 17, 1959 .1. VAN SLOOTEN ,8 9. S ELF-CONTAlNED' TYPEHYDRAULIC VALVE LIFTER Filed Nov. 22, 1954 INVENTOR United States PatentSELF-CONTAINED TYPE HYDRAULIC VALVE LIFTER Louis J. Van Slooten,Holland, Mich., assignor to General Motors Corporation, Detroit, Mich.,a corporation of Delaware Application November 22, 1954, Serial No.470,305

9 Claims. (Cl. 123-90) This invention relates to automaticallyextensible thrust transmitting devices such as hydraulic valve liftersused in the valve trains of internal combustion engines and the like,and particularly to such devices of the self contained type in which thefluid is sealed within the assembly with no provision for itsreplenishment from any external source during operation.

It is the principal object of the invention to provide an improvedlifter device of the aforementioned type employing a cylinder, a plungerand a bellows seal between the thrust transmitting end of the plungerand its associated end of the cylinder.

A more specific object of the invention is to provide such a sealingconstruction in the form of a metallic tubular bellows having piston andcylinder connecting means associated with the respective ends of thebellows which serve in a particularly advantageous manner to support theadjacent bellows pleats against excessive localized bending stresses inoperation.

A further object of the invention is to form the connecting meansbetween the cylinder member and its associated end of the bellows with arigid portion which serves both to protect the bellows from externalinjury and to prevent excessive movement of its piston associated end inthe direction tending to collapse the bellows.

- A still further object of the invention is to provide a bellows sealedhydraulic valve lifter which comprises a minimum number of parts oflight weight and simple design which can be economically manufacturedand assembled into a unit unsusceptible to damage in handling andcapable of long service in operation.

The means by which these and other objects of the invention are attainedwill be more clearly understood from the following description of apreferred embodiment, having reference to the drawing wherein:

Figure 1 is a sectional view of a portion of an internal combustionengine having a valve operating train incorporating my improved lifterdevice.

Figure 2 is an enlarged sectional view similar to Figure 1, showing theinternal construction of the lifter device.

Referring now in detail .to the drawing, there is shown in Figure 1 anengine cylinder block and crankcase structure designated generally bythe numeral 1 in which is located a working cylinder 2 having the usualpiston 3. Closing the upper end of the cylinder 2 and forming acombustion chamber 4 above the piston is a cylinder head 6. 'At 7 is apoppet valve controlling communication between a cylinder head port 8and the combustion chamber 4 and having a stem 9 slidably mounted forreciprocation in the cylinder head. In conventional manner, reciprocalmovements of the valve 7 are effected by rotation of a cam 11 which issuitably supported in they crankcase 1 and driven in timed relation withmovements of the piston 3. Completing the valve operating train, I haveshown my lifter 12 operatively engaging the cam 11 and slidablysupported for reciprocation in a lifter ice bore 13 formed in thecrankcase 1. Upward movements of the lifterare transmitted by the usualpush rod 14 to an adjusting screw 16 fixed in one end of the rocker 17,which latter is arranged to oscillate about an axis represented by therocker shaft 18 suitably supported on the cylinder head 6, the other endof the rocker being in driving engagement with the upper end of thevalve stem 9. A valve return spring 19 having one end secured to thevalve stem and its other end seated against the cylinder headserves tomaintain the valve in closed position as illustrated in Figure l.

As shown in Figure 2, the lifter 12 comprises telescoping cup-shapedcylinder and plunger members 21 and 22 arranged in nesting relation.Between the closed end of the cylinder 21 and the adjacent end of thelifter plunger 22 is a fluid pressure chamber 23 which is normallymaintained filled with fluid for transmitting thrust from the cylinderto the plunger during opening movements of the engine valve 7. Thispressure chamber includes a well- 24 which opens upwardly into anenlarged diameter portion 26 of preferably greater diameter than thebore 27 of the cylinder and extending upwardly on the lower end of theplunger outer periphcry. The lower end of the plunger has an extension28 of reduced diameter forming a shoulder 29 at its juncture with themain body to the plunger. Loosely journalled on the extension 28 andhaving an external flange 31 rotatably seated against the shoulder 29 isa cup-shaped cage member 32 whose end wall is provided with one or moreapertures 33 providing communication between the interior of the cagemember and the portion of the chamber 23 externally thereof. The sidewalls of the well 24 loosely fit the plunger biasing spring 34 whoseupper end loosely embraces the cage member 32 and maintains the flange31 of the cage seated against the shoulder 29 of the plunger. Extendingthrough the end or bottom wall of the plunger and its extension 28 is .afluid supply passage 36, through which fluid may pass to the pressurechamber 23 from reservoir 35 interiorly of the hollow plunger. A checkvalve accommodating such flow but preventing flow in the reverse orupward direction through the passage 36 is provided in the form of aball 37 which is of larger diameter than the passage 36. The seat ,forthis ball 37 is formed by the lower end of the plunger extension 28 andwhen the ball is in engagement with this seat and the cage flange 31 isin abutment with, the plunger shoulder. 29 only a predetermined smallclearance (on the order of .004-.008 in.) exists between the ball andthe bottom wall of the cage member.

Above the shoulder 29 the plunger side walls 40 have a close sliding fitin the cylinder bore 27. The cylinder bore 27 extends only a limiteddistance above the pressure chamber enlargement 26, the upper side walls41 of the cylinder being relieved on their internal periphery to form anannular extension 42 of the reservoir 35. The piston side walls 43 havetheir external periphery also relieved adjacent the open end and areprovided with one or more apertures 44 interconnecting the reservoir 35and its extension 42. The upper end of the plunger side walls 43terminate within the lower end of the reservoir extension 42, andresting on the open end of the plunger is a push rod seat member 45which serves to transmit plunger thrust to and forms a lower seat forthe push rod 14. This seat member 45 has a depending portion 46extending a short distance into and having a slip fit with the plungerupper side walls 43, the plunger thrust being taken by a shoulder 47surrounding this depending portion 46. The upper surface of the seatmember, including its central push rod seating surface 48 which ispreferably made concave as shown, and

the surrounding annular surface 49 which is preferably made flat areboth imperforate and form part of the sealing means preventingrescapeoffluid from theyliften device.

Also included in the sealing means is a rigid-member 50, convenientlyformed as-a sheet metal stamping, and including a tubular portion 51 anda flangeportion SZ. The tubular portion 51 is of a diameter largerthanthe push rod, 14 and extends coaxially of the cylinder a sufficientdistance inwardly thereof to serve as aplunger stop means limitingoutward movement of the plunger by abutment with the annularsurface 49'.The flange 52 which connects the upper end of thisitubulargportion to,the open end of the cylinder, as by a spinningror any other suitablesealed connection 53,: forms-.a;pocket 54 facing the annular surface49.-

- Adjacent one. marginal extremityofitherportion of the pocket 54 arethe opposite ends of a tubular bellws 56 which loosely surrounds thetubular portion-51; and :com

pleting the sealed connection between the-cylinder open,

end and the push rod seat 451111? upper and, lower annular bodies 57and, 58 of solder or other;rela tively 11OW' melting point metal inwhich the longitudinally out-turned: upper and lower flanged ends 59zandgtl, of the bellows It will be observed; thatthe lower end pleat 61ofthe bellows abuts the flatannularsurface- 49- are imbedded.

adjacent the recess 55, and the solderSS-in this'recess is ofsuch-depth-that its upper sunface-isr-flush withthe;

annulansurfaceil towcooperate in gsupporting the end Pleat 61.

avoided and its resultant-fatigue failure has beenpractically-.eliminated. Ill-addition, the arrangement whereby the bellows endfianges 60- and 59 are 'imbedded in thesolder further=ensures that allendwise loading of the, bellows is ;-substantially coaxial, whether intension or'-. compression, The provision of the recess SSand -the pocket54 -facilitate-convenient assembly of thebellows to the push rod seat 45and the rigid member 50 in production-since the depjosits =0f solder canbeinitially installed int-each, after which first one end of the bellowsandthen; the other maybe imbeddedwhile maintaining the .solder- Thespinning or crimping; of the sheet metal flange toforrn the connection-53;with the.

in molten condition.

cylindenis preferably doneafter completing the Sub-2&- sembly-of thelast three mentioned parts.

The tubular portion 51, in addition to serving as, a stop.,li1nitingcontraction of the bellows, shields the internal periphery of-rthebellows from external damageduring-handling of the lifter? and duringinsertion and removal of the push rod learn the engine. Thetubularportion 5l' also serves to support the bellows against anyabnormal: lateral deformation resulting -from i an excessive pressuredeveloping within the reservoir and its extension eliand the flangeportion 52 of thecsheet metal/stamping serves to cooperate with thetubular. portion in shielding the bellows upperrend against damage,

in handling.

While only a single preferred'embodiment of the invention has beendisclosed it is appreciated that numerous minor changes in-theconstruction and arrangement of the parts may be made without departingfrom the spirit Similarly, the upper-body .of, solder .SZ -is de positedto such a depth inthe pocket 54=as toprovide (a; fiat surface-62adjacent the bellowsend: flange 5940, abuttably support the upperend;pleat 63 ofthmbellovvs;

4 and scope of the inventionas defined in the following claims.

I claim:

1. In an automatically extensible and contractible thrust transmittingdevice of the self-contained-fluid typehavinga cylinder and a plungerreciprocable therein, a body'of fluid within the cylinder, said'cylinderand plunger having means respectively movable therewith presentingfacing longitudinally spaced apart surfaces, one of said surfaces beingformed at least in part by a body of relatively low melting pointmaterial, and a bellows expandible longitudinally of the cylinder-havingat least one of its ends defined by a surface facing and parallel tosaid one surface .andaflange, said bellows surface being in abutmentwith said one surface and said flange being embedded in said material.

2. In an automatic longitudinally adjustable thrust transmitting devicecomprising slidably interfitted plunger and cylinder members, a body offluid for transmitting thrust between the plunger member and one end ofsaid cylinder member, at least one of said members having side wallsdefining a reservoir for fluidto be supplied to and returned from saidbody with change in length of said device, a stop member limitingmovement of the plunger member away from said, body, saidrstop, memberand-the other'of said first two namedmembers having facing surfaces inlongitudinally spaced apart relation, each of said surfaces being formedat "least in part by a body of relativelytlow melting point material,and a tubular bellowshaving endpleatsiabutting said surfaces andlongitudinally extending flanges embedded in said material.

3, Ahydraulic valve lifter of the self-contained-fluid type comprisinggenerally cup-shaped cylinder and plunger members in slidably nestingrelation and-forming a fluid pressure chamber between their respectiveend walls, an imperforate push rod seat abutting the open end of theplunger member, a push rod seat retainer having an elongated portionextending longitudinally of the cylinder member above said push rod seatand an imperforate flange connected to the open end of the cylindermember in a sealing relationship, an annular body of relatively lowmelting point metal bonded'to both said push rod seat and said flange,and a-tubula'r bellows looselysurrounding said elongated portion havingend pleats abutting said annular bodies and terminating with oppositelydirected longitudinally extending flanges embedded in said annularbodies.

4. A hydraulic valve lifter of the self-contained-fluid type comprisingnesting generally cup-shaped cylinder and plunger members havingslidably interfitted side wall portions spaced inwardly from theirrespective open ends and radially spaced other side wall portionsadjacent their open ends, an imperforate push rod seat abutting the openend of the plunger member having an annular surface facing outwardly ofthe cylinder member, said surface having an annular recess therein; apush rod seat retainer including a tubular portion extending into thecylinder member and a flange portionsealingly connected to said otherside Wall portion of the cylinder member, said tubular and flangeportions forming an annular pocket at their juncture facing said recess,an annular body of low melting point material within said recess andbonded therein to said push rod,

type having a cylinder member open at one end, a hollow plungerreciprocable therein and having its corresponding end open and spacedinwardly of'the cylinder member from said cylinder member end, saidplunger having its open end defining side Walls radially spaced from theopen end defining side walls of the cylinder member, said plunger sidewalls being apertured to provide communication between the interior ofthe plunger and the open end of the cylinder member, and means sealingthe cylinder member open end to the plunger open end and limitingmovement of the plunger outwardly of the cylinder member, said meansincluding a rigid tubular member extending into the open end of thecylinder member, a push rod seat socketably fitting the plunger open endand having an imperforate annular surface facing the extended end ofsaid tubular member, said tubular member having an out-turned flange atits other end sealingly connected to the cylinder member open end, and atubular bellows loosely embracing said tubular member and bonded at itsrespective opposite ends to said surface and said flange.

6. A hydraulic valve lifter of the self-contained-fiuid type having acylinder member open at one end, a hollow plunger reciprocable thereinand having its corresponding end open and spaced inwardly of thecylinder member from said cylinder member end, said plunger having itsopen end defining side walls radially spaced from the open end definingside walls of the cylinder member, said plunger side walls beingapertured to provide communication between the interior of the plungerand the open end of the cylinder member, and means sealing the cylindermember open end to the plunger open end and limiting movement oftheplunger outwardly of the cylinder member, said means including a rigidtubular member extending into the open end of the cylinder member, apush rod seat socketably fitting the plunger open end and having animperforate annular surface facing the extended end of said tubularmember, said annular surface being relieved adjacent one marginalextremity thereof by an annular recess, said tubular member having anoutturned flange at its other end sealingly secured to the cylindermember open end, an annular body of solder substantially filling saidrecess and bonded therein to said push rod, an annular body of solderbonded to said flange and defining a surface facing said annularsurface, and a tubular bellows having end pleats abutting said surfaces7 and terminating with longitudinally extending flanges embedded in saidbodies of solder.

7. In a hydraulic valve lifter having nestably associated cup-shapedplunger and cylinder members defining a chamber for a thrusttransmitting body of fluid between their respective end walls and areservoir above the plug er end wall for fluid entering and leaving saidchamber, said plunger and cylinder members having their side wallsadjacent their open ends radially spaced from each other, a push rodseat member abutting the plunger open end and having an imperforate pushrod seating surface and a surrounding imperforate flat annular surfaceboth facing outwardly of the cylinder member, a sheet metal retainermember including a tube extending longitudinally of the cylinder memberhaving one end abuttable with said annular surface adjacent said seatingsurface and its other end provided with an external flange overlying thespace between said plunger and cylinder side walls, said flange beingsealingly secured to the cylinder member open end, and a tubular bellowssealingly interconnecting said annular surface and said flangeexternally of said tube, one of said plunger and retainer members havinga passageway for flow of fluid between said space and the interior ofthe plunger member.

8. In a hydraulic valve lifter including a cylinder open at one end, aplunger reciprocable in the cylinder, and means for sealingly closingthe open end of the cylinder including a tubular member disposed betweenthe plunger and the open end of the cylinder and longitudinallyextensible in response to plunger reciprocation-relative to thecylinder, and a rigid member fixed to the cylinder member outwardlythereof from said tubular member and having a tubular portion extendinginwardly of and shielding the internal periphery of said tubular member,said tubular portion being open at both ends to accommodate passagetherethrough of external means in thrust transmitting relation with theplunger.

9. The invention defined in claim 8, wherein the plunger adjacent end ofsaid tubular portion is operatively abuttable with the plunger to limitplunger movement outwardly of the cylinder.

References Cited in the file of this patent UNITED STATES PATENTS2,096,257 Moorhouse Oct. 19, 1937 2,109,809 Van Ranst Mar. 1, 19382,153,097 Moorhouse Apr. 4, 1939 2,278,963 Arola Apr. 7, 1942 2,553,756Engemann May 22, 1951 2,689,555 Van Slooten Sept. 21, 1954 2,746,437 VanSlooten .4. May 22, 1956 FOREIGN PATENTS 121,417 Australia May 16, 1946

